Collaborative research at UM expected to improve LED technology and slash cost

A research project jointly
conducted by the University of Macau (UM), Nanjing Tech University, and Nanyang
Technological University, Singapore, has achieved a significant breakthrough,
laying a theoretical foundation for materialising high-efficiency and low-cost
perovskite light emitting diode (LED). The related finding has been
published in Nature Communications.
The research can help to significantly improve the luminous efficiency of
perovskite LED and have the potential to bring low-cost, high-efficiency LED
displays and LED light sources into daily life.

Researchers from the three
universities discovered that the slow bimolecular recombination that drives
three-dimensional lead-halide perovskites’ outstanding photovoltaic performance
is conversely a fundamental limitation for electroluminescence. By probing the
microscopic carrier dynamics with femtosecond laser spectroscopies, the slow
bimolecular recombination limitation can be overcome by tailoring the
three-dimensional perovskites into van-der-Waals-coupled Ruddlesden-Popper
perovskite multi-quantum-wells. High-efficiency electroluminescence can be
achieved with this new type of perovskites. The research project was jointly
led by Dr
Xing Guichuan, assistant professor from UM’s Institute of Applied
Physics and Materials Engineering; Prof Huang Wei, president of Nanjing Tech
University; and Prof Sum Tze Chien from Nanyang Technological University.

According to Dr Xing,
the newest technology available on the market is organic light emitting diode
(OLED). Because of the low-temperature solution processability, large range
emission colour tenability, and low cost, the perovskites are promising
alternatives to the organic molecules for LED applications. UM’s research can
help to significantly improve the luminous efficiency of perovskite LED and
promote the development and commercialisation of this technology.

Dr Xing is one of the initiators of the research
in the application of this new type of perovskites. In 2014, the paper
first-authored by him, titled, ‘Low-temperature Solution-processed
Wavelength-tunable Perovskites for Lasing’, was published in Nature Materials. It has been cited more
than 600 times. Another paper first-authored by him, titled ‘Long-range
Balanced Electron-and Hole-transport Lengths in Organic-inorganic CH3NH3PbI3’,
was published in Science magazine in
2013, and has been cited over 1,800 times. In 2016, he received the PVSEC-26
Young Scientist Award, in recognition of his outstanding contributions to the
research in perovskite optoelectronics.